This article is for informational purposes only and is not financial advice. TheGatBull may earn a commission from some links at no cost to you — see our disclosure and full disclaimer.
Not financial advice. This is a market-watch guide from Seoul, not a recommendation.
On the day Nvidia reports earnings, a US investor watches the after-hours quote for NVDA jump around on a screen. But the companies that sell Nvidia its HBM (high-bandwidth memory — the stack of chips that feeds an AI accelerator), namely SK Hynix and Samsung Electronics, have their ordinary shares move somewhere off that screen first. In Seoul, while America sleeps.
This is one of those weeks. Nvidia reports right after the US close on Wednesday, August 26 — which is about 5:20 a.m. Thursday, August 27, in Seoul. And the Korea Exchange (KRX) opens three hours and forty minutes later, at 9:00 a.m. The New York regular session does not reopen until roughly thirteen and a half hours after that. In other words, one of the major cash equity markets that digests Nvidia’s guidance first is Seoul.
And that Thursday morning, Seoul does not get just the one thing. The same morning, the Bank of Korea’s Monetary Policy Board sets the base rate (currently 2.75%), and the same day in the US, the Jackson Hole symposium opens. It looks as if the calendar shoved three things into one box by accident. It did not — structurally, Thursday is the busiest morning Korea has all year.
🎩 What this means for EWY / global-ETF holders. If you hold EWY (the iShares MSCI South Korea ETF), its top two names — SK Hynix and Samsung Electronics, together roughly half the fund — get repriced first in Seoul on Nvidia’s earnings Thursday. Your EWY starts reflecting that number before America reacts. For better or worse.
Why three of them landed in one box
First, the clock. Everything below is Korea Standard Time (KST).
| Time (Thu Aug 27, KST) | Event | Why it matters to Seoul |
|---|---|---|
| ~05:20 a.m. | Nvidia earnings print (right after the US Aug 26 close, ≈16:20 ET) | Next-quarter demand signal for HBM suppliers SK Hynix and Samsung |
| 9:00 a.m. | KRX regular session opens | The Nvidia number gets traded in cash for the first time |
| morning | Bank of Korea rate decision + revised outlook + Governor’s press conference | Domestic monetary policy — the won, bank stocks, growth-stock valuations |
| day/night (US Aug 27) | Jackson Hole symposium opens (Aug 27–29) | The Fed’s stance — the global dollar and risk assets |
| 10:30 p.m. | New York regular session opens | America finally reacts in cash |
Two axes overlap. One is the global axis (Nvidia demand plus the Fed at Jackson Hole); the other is the domestic axis (the BOK rate). Seoul’s Thursday session has to price both at once. And because America is still asleep, Seoul moves with no US close to lean on.
🎩 Under the Gat. Trading “first” sounds like an edge, but soberly it is also the right to be wrong first. Before the price settles, Seoul wears the noise first. Last month (2026-07-29) SK Hynix posted a record quarter and the stock still swung from +4% to −20%. Whether the time gap is an information edge or a volatility exposure gets decided in Seoul that morning.
What a US reader actually sees — three ways to watch
There are roughly three ways to “watch” this Thursday from a US account. Not a buy suggestion — a map of what you see, and where.
1) After-hours NVDA (US Wednesday evening). Fastest, but this is Nvidia’s own reaction, not Korea’s. If Nvidia rises, it signals “AI demand exists”; whose revenue that demand lands on is not yet visible here.
2) Seoul cash shares (Thursday morning, while the US sleeps). The ordinary shares of SK Hynix and Samsung price Nvidia’s guidance into cash for the first time. To buy KRX ordinary shares from a US retail account you would have to reach the Korean market directly through something like Interactive Brokers. For most US readers this is a live viewing screen, not a trading one.
3) US-listed proxies (Thursday night, after the New York open). This is where actual buying opens. SK Hynix trades on the Nasdaq under the ticker SKHY, and the whole Korea exposure is available through EWY (the iShares MSCI South Korea ETF). One caution — these are theme proxies, not the same instrument. SKHY (an ADR) and the Seoul ordinary shares have shown a large premium gap — the ADR recently traded at a 43% premium to the Seoul shares, a case we covered — and EWY is a basket, not a single name.
Here is the point. Buying Nvidia is a bet on “AI demand exists.” Watching Seoul shows you which company’s revenue that demand actually becomes. The first is a theme. The second is an invoice.
🎩 Under the Gat. “Buying Korean semiconductors” is imprecise. You are buying two companies. And on Thursday morning, those two companies receive Nvidia’s invoice before Wall Street even opens it. (For how differently those two names behave, see Samsung and SK Hynix Are Not the Same Trade.)
The trap — “trading first” is not “trading right”
Three things to watch out for.
First, the domestic and global axes can cancel each other. Say Nvidia’s guidance is strong and chips want to rise — but the BOK hikes the same morning (part of the market expects it), which is a headwind for growth-stock valuations. When the two signals point opposite ways, Thursday’s index cannot pick a direction.
Second, the Korean market tends to be decided by a handful of days. Over the last few weeks, most of a given week’s return came from two or three sessions (a pattern our weekly scoreboard keeps confirming). Which means one Thursday can be the whole week — up or down.
Third, the recent backdrop is already loud. On the immediately preceding Monday (August 24), the KOSPI fell 3.12% and gave up the 6,700 line, and Samsung Electronics closed down 8.79% (on the day’s move) on the first trading session after announcing a ₩90–110 trillion shareholder-return plan. Today, Tuesday (August 25), the market looked calmer — the KOSPI rebounded 0.68% to 6,742.74 and the KOSDAQ rose 1.70% to 827.15 — but it was a wide-swing day: the KOSPI dropped as low as 6,408.82 intraday before recovering. In other words the market walks into Thursday already jumpy — primed to move hard on a small signal, on the very morning three events collide.
(A note on the numbers: the Aug 24 and Aug 25 closes and percentage moves are on the KRX regular-session 15:30 close. The Aug 25 values were sourced directly from a market data feed and back-checked against the prior close. The intraday low is an intraday value, not a close.)
And Thursday is not the end — August 31
There is one more thing on the watch calendar. MSCI’s August review takes effect at the August 31 (Monday) close. The constituents of the index EWY tracks (MSCI Korea 25/50) change mechanically that day, and passive money moves with them. So Thursday (Aug 27) moves on news, and the following Monday (Aug 31) moves on rules. If you hold EWY, both dates are worth marking. (For what goes in and out on Aug 31, see If You Own EWY, You Are Already Buying on August 31.)
🎩 What to watch Thursday morning. One tell sits above the rest: if Nvidia’s guidance is strong but Seoul does not follow at the 9:00 open — SK Hynix and Samsung flat or down — that is the domestic axis (a possible BOK hike) fighting the global one. When the two axes agree, the index runs; when they split, it stalls.
This is a market-watch guide, not investment advice. It is watching information, not a buy or sell recommendation. Currencies are shown in both ₩ (won) and $ (dollar); the Aug 24–25 closes are on the KRX regular-session 15:30 Seoul close.
Sources: Bank of Korea MPB schedule and decision (BOK) · Nvidia IR earnings calendar · Jackson Hole symposium (KC Fed) · MSCI August review (MSCI) · KRX regular-session close · iShares EWY fact sheet.
Frequently Asked Questions
On Nvidia’s earnings day, does Korea really trade “first” in the world?
More precisely: Nvidia reports right after the US close (about 16:20 ET). NVDA itself trades immediately in US after-hours, but among the large regular equity markets where the chip suppliers’ ordinary shares actually open, Seoul is near the front — the Korea Exchange opens at 9:00 a.m. KST, about 3 hours 40 minutes after the print. Tokyo opens at the same hour, but Seoul’s reaction is more direct because it holds the HBM suppliers (SK Hynix, Samsung) themselves. So “before the US” is the accurate phrasing, rather than “first in the world.”
What do SK Hynix and Samsung sell to Nvidia?
HBM (high-bandwidth memory) — the high-performance memory that sits on Nvidia’s AI accelerators, of which the two companies supply a large share of the world’s total. SK Hynix is the market leader, and Samsung is certified as a supplier for Nvidia’s next generation (HBM4). That is why Nvidia’s demand guidance reads as a leading signal for these two companies’ next-quarter revenue.
What can I actually do from a US account this Thursday?
Live viewing is via the Seoul cash shares (reachable through a broker such as Interactive Brokers); actual buying opens after the New York open, through SKHY (the SK Hynix ADR on the Nasdaq) or EWY (the Korea basket). But an ADR or an ETF is a proxy, not the same instrument — there are premium gaps and basket-composition differences. This is a watch map, not investment advice.
Will the Bank of Korea raise or hold on August 27?
From the current 2.75%, market expectations are split — some houses see a hike, others a hold. The decision and the Governor’s press conference we cover in Saturday’s What Seoul Said.
This article is for informational purposes only and is not financial advice. TheGatBull may earn a commission from some links at no cost to you — see our disclosure and full disclaimer.
